A light emitting diode (“LED”) is a lighting semiconductor device capable of converting electrical energy to light. With recent improvements in luminous output from an LED, conventional lighting apparatus such as incandescent light bulbs and/or fluorescent lamps are likely to be replaced with LEDs in the foreseeable future. Various commercial applications of LEDs, such as traffic lights, automobile lightings, and electronic billboards, have already been placed in service.
An LED is a semiconductor diode with a biased p-n junction capable of emitting narrow-spectrum of electroluminescence. For example, when a current passes through the LED, it emits light. The light is essentially a form of energy releasing when electrons and holes are recombined. While the wavelength of emitted light may vary depending on the composition of materials, the amount of light that can be produced also depends on various parameters such as current availability across the LED.
To increase light output, a conventional approach is to increase current flow to the LED. A conventional approach, for example, deposits a heavy and/or thick electrically conductive layer over an LED to increase current distribution. A drawback, however, associated with this conventional approach is that although the thick electrical conductive layer can provide additional current flow, it also hampers light from passing through the electrical conductive layer partially due to its thickness.